In order to maintain consumer confidence that diamond products are properly disclosed, it is important that the diamond industry has practical methods for testing cut gemstones to determine whether they are natural diamonds, synthetic diamonds or simulants. Similarly it is important that it has methods for determining whether a diamond has been artificially treated, for example to change its colour.
Apparatus exist that are capable of distinguishing diamond gemstones from simulants, and for measuring a parameter of a diamond to give an indication of whether the diamond is likely to be natural or synthetic, or whether it has been treated, for example to improve its colour. Typically, such apparatus perform a measurement, then place diamonds in respective bins dependent on the result of the measurement. However, such apparatus are often unreliable and further tests and/or measurements are often required to confirm whether or not a gemstone is a diamond and, if so, whether it is natural or synthetic and/or has been treated.
Additionally, the determination of other physical parameters of a gemstone, such as colour, size and cut, is an important process in the diamond industry.